The potential energy of a freely falling body continuously decreases.

Question

The potential energy of a freely falling body continuously decreases.

1. A. The principle of conservation of energy is violated
2. B. The principle of conservation of energy is not violated (Correct answer)
3. C. Gravitational force is violated
4. D. Gravitational force is not violated

Correct Answer

Option B — The principle of conservation of energy is not violated

Detailed Solution & Explanation

The correct answer is The principle of conservation of energy is not violated.

Key Points

• When a body falls freely, its potential energy decreases continuously, but this does not violate the law of conservation of energy, because the lost potential energy is converted into kinetic energy.
• At any point during the fall, the total mechanical energy remains constant:
• Total energy = Potential energy (mgh) + Kinetic energy (½mv²) = constant.
• At the highest point the body has maximum potential energy and zero kinetic energy; as it falls, h decreases so PE falls, while v increases so KE rises by exactly the same amount.
• Just before striking the ground, the energy is almost entirely kinetic.
• The law of conservation of energy states that energy can neither be created nor destroyed but only transformed from one form to another, and the total energy of an isolated system remains constant.

Exam Tip

• in the presence of air resistance, mechanical energy is not conserved in the mechanical sense, but total energy still is, since the difference appears as heat and sound.

प्रश्न (हिन्दी में)

मुक्त रूप से गिरते हुए पिण्ड की स्थितिज ऊर्जा लगातार कम होती जाती है।

1. A. ऊर्जा संरक्षण सिद्धान्त का उल्लंघन है।
2. B. ऊर्जा संरक्षण सिद्धान्त का उल्लंघन नहीं है।
3. C. गुरूत्वाकर्षण बल का उल्लंघन है।
4. D. गुरुत्वाकर्षण बल का उल्लंघन नहीं है।